Floyd County Emergency Management said four people were injured at the Rome River Jam concert in Rome when part of a tree fell on them just before 6 p.m.
Emergency officials said two people refused treatment but two others were transported to hospital.
There is no word either of their conditions.
Severe Weather Team 2s Brad Nitz said storms can produce winds of up to 60 mph in the Atlanta metro.
Nitz said at 6 p.m. there were already numerous reports of trees down in the Elijay area.
The whole Atlanta metro area has been placed under a severe thunderstorm watch until 11 p.m.